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[ih] Internet addressing history section

    > From: Paul Ruizendaal

    > There was no broadcast-based discovery of other gateways on the same
    > local net(s).

There _weren't_ any LANs in the very earliest Internet (although packet radio
networks were close); that why the earliest IP address had only 8 bits of
'network number', to support the small number of WANs.

    > the PUP Gateway Information Protocol, which in turn seems to have been
    > influenced by the routing protocols used inside IMP's.

The very earliest ARPANET routing protocol, perhaps - both it, and the Xerox
routing protocols, were Destination Vector. The ARPANET transitioned to a
Link State design fairly early. I'd have to check the dates for PUP, and that
transition; my my sense is that the latter happened first.

    > RIP for tcp/ip itself was only codified in an RFC in 1988; not sure why
    > it took 5 years to do so.

A number of reasons, but part of it was a feeling on some people's part (e.g.
me) that DV algorithms had been shown by the ARPANet work to have issues. The
BBN report by McQuillan et al that introduced the idea of LS (might have been
"ARPANet Routing Algorithm Improvments", No. 3803 - I can't find my copy)
went into great detail about the problems they were seeing with DV

In retrospect, the concern over DV was probably excessive; the original
ARPANET routing was load-sensitive, so the inputs to the path selection were
orders of magnitude more dynamic, which probably forced a lot of the DV issues
out into the light.